Starting position: Feet should be shoulder width apart, toes pointing out just slightly. Back is straight and core is tight. The kettlebell is resting comfortably between the legs.
The next step would be a quick bend to gain momentum. The bend should start at the hips as if you are beginning to sit down. The backwards drive can be a short as the first image or more profound if necessary, like the second image. Be sure to keep your core tight.
Next you will want to use the momentum from the backwards drive to "thrust" forward, the power from this should be primarily generated by your hips. Using the thrust, let the kettlebell begin it's ascent.
The final position will be with the kettlebell overhead. Your arms should be as straight up as possible and have passed the ears.